Many medical procedures involve joining tissue pieces. Suturing adjacent tissue pieces is commonly performed using suture, particularly where the tissue pieces are easily accessible to the surgeon. In conventional surgical techniques, the surgeon will secure the tissue pieces by forcing a needle and suture material through various portions of the tissue, and then tying a knot in the suture material to secure the tissue pieces.
Minimally invasive surgical techniques have emerged as an alternative to conventional surgical techniques to perform a plurality of surgical procedures. Minimally invasive procedures differ from conventional surgical procedures in that a plurality of devices may be introduced into the body through a small incision. As a result, trauma to the body is greatly reduced, thereby decreasing the recovery time of the patient.
Percutaneous and other minimally-invasive methods of surgery, where the surgery may be performed remotely via catheters, often include the need to fasten tissue pieces which the surgeon cannot directly access. For example, in percutaneous operations to close a patent foramen ovale (PFO), adjacent tissue pieces on either side of the PFO must be secured together via a catheter. Further description of such PFO procedures is included in co-pending patent application Ser. No. 11/174,143, filed concurrently herewith and entitled “System, Apparatus, and Method for Repairing Septal Defects,” the entire contents of which are expressly incorporated herein by reference.
One challenge presented when performing a heretofore conventional surgical procedure using a minimally invasive technique is to remotely position and secure sutures to an area of interest. In minimally invasive surgical techniques the surgeon's access to the approximation site is greatly reduced. One method involves using a surgical device to attach the suture material to the tissue, while allowing for sufficient suture so that the suture ends lead outside of the patient's body for easy access by the surgeon. The surgeon can remotely form a loose knot in the suture material and advance the knot to the tissue within the patient using a so-called “knot pusher.” The surgeon can then remotely tighten the suture and knot, thereby securing the tissue pieces together.
Several knot pushing devices are known which permit an operator to push suture knots which have been formed extracorporeally towards tissue to be sutured. For example, U.S. Pat. No. 5,769,863, issued to Garrison et al., discloses a surgical knot pusher having an elongated body connected to a pushing head. The pushing head engages a portion of suture material containing a knot and is advanced to the area of interest, thereby “throwing” the knot. Once the suture knot is placed the knot pushing device is removed and a cutting implement is introduced into the body and cuts the remaining suture material. The remaining suture material is then removed. Another example of a knot pusher is disclosed in U.S. Pat. No. 6,860,890, entitled “Surgical Knot Pushing Device and Method of Use,” the entire contents of which are expressly incorporated herein by reference.
In light of the foregoing, there is presently a need for improved systems for remotely securing tissue pieces. More specifically, there is a present need for an improved method, apparatus, and system for fastening tissue. The current invention meets this need.